In a conventional precast concrete (PC) member connection method, high-strength mortar is injected into empty oval spaces of PC member connection parts and rebars of PC members are interconnected at spliced parts. According to the above-described connection method, since the high-strength mortar is cured at the spliced parts, instantaneous coupling force may not be ensured and connection performance greatly differs depending on the quality of curing.
In another conventional PC member connection method, connection members called ductile rods are embedded and a PC member to be coupled is bolted to screw holes of the connection members (at least four screw holes in PC connection surfaces) on site. However, the center locations of the screw holes facing each other to be bolted together should be very accurate. That is, tolerance may not be achieved for on-site errors of PC technology and thus much effort and time are required for accurate location management.
In another conventional PC member connection method, brackets are integrally provided on a column and hardware to be connected to the brackets is provided on a girder or beam, thereby coupling the column and the girder together. However, the above-described coupling structure is applicable only to non-finished parts due to protrusions such as the brackets. In addition, connection parts between PC members have little resistance against lateral force and are defenseless against lateral force generated during construction.
A background technology of the present invention is disclosed in KR 1058540 entitled “Dry Joint Structure of Precast Concrete Beam and Column Unit with Bolt Connector”. This background technology discloses ‘a PC column-to-girder connection structure including a PC column 10 having embedded rebars 12 therein and having coupling holes 13 at a certain height of a body to expose screw holes 23′ on a side surface thereof, and PC girders or beams 11 and 11′ in which ends of rebars 14 are embedded and from which other ends of the rebars 14 horizontally protrude, wherein the PC column 10 and the PC girders 11 and 11′ are connected to each other by coupling threaded bars 20 to ends of the screw holes 23′ through through-holes 19 of duct pipes 18 fixed to -shaped angles 17 provided at ends of the PC girders 11 and 11′ as illustrated in FIG. 6A.
However, in the above background technology, high-strength mortar is injected into empty oval spaces 6 of PC column connection parts and rebars of PC members are interconnected at spliced parts. According to the above-described connection method, since the high-strength mortar is cured at the spliced parts, coupling force may not be ensured instantaneously and connection performance greatly differs depending on the quality of curing.
In addition, connection members called ductile rods 7 are embedded in a PC member and another PC member to be coupled is bolted to screw holes 9 of the connection members (at least four screw holes in PC connection surfaces) on site.
However, the center locations of the screw holes facing each other to be bolted together should be very accurate. That is, tolerance may not be achieved for on-site errors of PC technology and thus much effort and time are required for accurate location management.
Another background technology of the present invention is disclosed in KR 1071273 entitled “Precast Concrete Column”. This background technology discloses ‘a PC column including a PC body extending in a vertical direction, a plurality of rebars embedded in the PC body along a length direction of the PC body, a supporting member provided along the length direction of the PC body, wherein at least one of top and bottom ends thereof is embedded in the PC body and a center part thereof is exposed to configure an exposed connection part, and a connection unit including a plurality of joint members coupled to the exposed connection part of the supporting member so as to be connected to PC girders or beams provided in horizontal directions, wherein the joint members are spaced apart from one another to face each other, and each includes a pair of connection parts having a plurality of through-holes into which bolts are inserted, at locations corresponding to each other, and wherein an insertion part extends along the length direction of the PC body between the pair of connection parts such that an end of the PC girder is inserted into the insertion part’ as illustrated in FIG. 6B.
However, in the above background technology, continuity in the sectional properties of the PC column and the girders and the tensile capacity of rebars therein may not be ensured, and slab and wall rebars may not be easily coupled to the PC member.